Alarm



1,643,870 S 1927' c. A. BLACKBURN ALARM Filed Dec. -5 1926 fa, m. B m%m WITNESS ATTORNEY Patented Sept. 27, 1927.

UNITED STATES PATENT OFFICE.

ALARM.

Application filed December 3,1926.

This invention relates to an alarm for liquid tanks and receptacles, the general object of the invention being to provide means for automatically causing the alarm to operate when the liquid level in the receptacle reaches a oint where the tank or receptacle is almost ull so as to prevent running over of the receptacle.

Another object of the invention is to provide a mechanically operated alarm, with means for causing the alarm to operate twice if the receptacle is not emptied after the first operation of the alarmj This invention also consists in certain other features of construction and in the combination and arrangement of the several parts, to be hereinafter fully described, illustrated in the accompanying drawings and specifically pointed out in the appended claim.

In describing, my invention in detail, reference will be had to the accompanying drawings wherein like characters denote like or corresponding parts throughout the several views, and in which Figure 1 is an elevation with parts broken away, showing the invention in use.

F1 are 2 is a lan view of the device with the oat omitte Figure 3 is a vertical sectional view through the alarm device.

In these views, 1 indicates a casing which contains a spring motor 2, the spring 3 of which is adapted to be wound by the key 4 which extends through a hole formed in the casing. The last gear of the train of gears of the motor engages a pinion 5 to which a vertical shaft 6 is connected, the shaft passing through a hole in the top of the casing and havin its upper end bent at right angles to orm the horizontal part 7. As will be understood, when the device is in operation, a very distinct clanging noise will be produced, due to the vibration caused in the casing by the horizontal part 7 of the vertical shaft 6, striking the closed loop 12 of the rod 8 at each revolution. The rod 8 has one end pivotally connected to the ears 9 punched from the top of the casing land the other end of the rod is bent downwardly, as at 10, and has a float 11 attached thereto, this float being adapted to be placed in a tank or receptacle A, the liquid in which Serial No. 152,467.

must be emptied at intervals in order to pre vent it overflowing. The rod 8 is formed with a closed loop 12 which extends downwardly and engages the part 7 of the shaft 6 when the rod is in its lowest position. The part 12 also acts as a rest for limiting the downward movement of the rod by resting upon the top of the casing.

From the foregoing it will be seen that movement of the motor is prevented by the part 12 engaging the bent end of the shaft 6 as long as the float is in lowered or partly lowered position. However, when the water or liquid rises in the tank A to a level adjacent the top of the tank, it will carry the float up with it so that the rod 8 will be moved to the dotted line position shown in Figure 1 so that the part 12 will free the bent end of the shaft 6 and thus permit the motor to operate and the noise, caused by vibration induced by the moving parts of the motor, will act as a warning that the tank or receptacle needs emptying.

As will be seen, the lower end of the part 12 is rounded so that when the bent end of the shaft 6 engages this rounded part, the motor will be strong enough to cause the bent end of the arm to push the rod upwardly so that the motor will operate to give the warning, but when the spring of the motor is partly unwound, it will not have strength enough to resist the weight of the float parts and thus the motor will cease to operate. As soon as the water or liquid moves the float parts to almost free the shaft 6, the weight of the float parts will be diminished to the extent that the strength of the motor will cause it to again come into operation and thus give a second warning.

It is thought from the foregoing description that the advantages and novel features of my invention will be readily apparent.

I desire it to be understood that I may make changes in the construction and in the combination and arrangement of the several parts, provided that such changes fall within the scope of the appended claim.

hat I claim is A liquid level alarm comprising a spring motor, a shaft driven by the same and having a horizontally extending part, a float rod having a projecting part formed with a rounded end, said projecting part engaging the horizontal part of the shaft to prevent operation of the motor-until the rod is raised by a float connected With the rod, the rounded end of the projection on the rod permitting the motor to operate as soon as the horizontal part of the shaft reaches the rounded end until the spring of the motor is partly unwound and then when the rod is lifted to a position to almost free the shaft from its projecting part, the motor will op- 10 erate for the second time.

In testin'iony whereof I atiix my signature.

CLIFTON A. BLACKBURN. 

